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971.
A novel fluorescent label based on organic dye-doped silica nanoparticles for HepG liver cancer cell recognition 总被引:2,自引:0,他引:2
In this paper, we report a method for the recognition of HepG liver cancer cells with the use of a novel fluorescent label based on organic dye-doped fluorescent silica nanoparticles. The novel organic dye-doped silica nanoparticles are prepared with a water-in-oil microemulsion technique. The silica network is produced by the controlled synchronous hydrolysis of tetraethoxysilane and 3-amino-propyltriethoxysilane (APTES). The organic dye fluorescein isothiocyanate is doped inside as a luminescent signaling element, through covalent bonding to the amino group of APTES. The organic dye-doped core-shell nanoparticles are highly luminescent and exhibit minimal dye leaching and excellent photostability. A novel fluorescent label method based on biological fluorescent nanoparticles has been developed. The dye-doped fluorescent silica nanoparticles are covalently immobilized with anti-human liver cancer monoclonal antibody HAb18. We have used antibody-labeled fluorescent nanoparticles to recognize HepG liver cancer cells. It has been observed that the bioassay based on the organic dye-doped nanoparticles can identify the target cells selectively and efficiently. The fluorescent nanoparticle label also exhibits high photostability. 相似文献
972.
973.
Pressurized capillary electrochromatography (pCEC) was coupled with electrospray ionization mass spectrometry (ESI-MS) using a coaxial sheath liquid interface. It was used for separation and analysis of peptides and proteins. The effects of organic modifier and applied voltage on separation were investigated, and the effects of pH value of the mobile phase and the concentration of the electrolyte on ESI-MS signal were investigated. The resolution and detection sensitivity with different separation methods (pCEC, capillary high-performance liquid chromatography) coupled on-line with mass spectrometry were compared for the separation of a peptide mixture. To evaluate the feasibility and reliability of the experimental setup of the system, tryptic digests of cytochrome c and modified protein as real samples were analyzed by using pCEC-ESI-MS. 相似文献
974.
975.
Yiping?Duan Anil?SaigalEmail author Robert?Greif Michael?A.?Zimmerman 《Materials Research Innovations》2003,7(1):10-18
In many applications of polymers, impact performance is a primary concern. Impact tests experimentally performed on molding
prototypes yield useful data for a particular structural and impact loading case. But, it is generally not practical in terms
of time and cost to experimentally characterize the effects of a wide range of design variables. A successful numerical model
for impact deformation and failure of polymers can provide convenient and useful guidelines on product design and therefore
decrease the disadvantages that arise from purely experimental trial and error. Since the specimen geometry and loading mode
for multiaxial impact test provides a close correlation with practical impact conditions and can conveniently provide experimental
data, the first step of validating a numerical model is to simulate this type of test. In this paper, we create a finite element
analysis model using ABAQUS/Explicit to simulate the deformation and failure of a glassy ABS (acrylonitrile-butadiene-styrene) polymer in the standard ASTM D3763 multiaxial impact test. Since polymers often exhibit different behavior in uniaxial tensile
and compression tests, the uniaxial compression or tensile tests are generally not representative of the three-dimensional
deformation behavior under impact loading. A hydrostatic pressure effect (controlled by the parameter γ) is used to generalize
a previously developed constitutive model ("DSGZ" model) so that it can describe the entire range of deformation behavior
of polymers under any monotonic loading modes. The generalized DSGZ model and a failure criterion are incorporated in the
FEA model as a user material subroutine. The phenomenon of thermomechanical coupling during plastic deformation is considered
in the analysis. Impact load vs. displacement and impact energy vs. displacement curves from FEA simulation are compared with
experimental data. The results show good agreement. Finally, equivalent stress, strain, strain rate and temperature distributions
in the polymer disk are presented.
Electronic Publication 相似文献
976.
Special decentralized control problems in discrete-time interconnected systems composed of two subsystems 总被引:4,自引:0,他引:4
In this paper, some special decentralized control problems are addressed for discrete-time interconnected systems. First it is pointed out that some subsystems must be unstable to ensure stability of the overall system in some special cases. Then a special kind of decentralized control problem is studied. This kind of problem can be viewed as harmonic control among independent subsystems. Research results show that two unstable systems can generate a stable system through some effective cooperations. In addition, a decentralized controller design method based on linear matrix inequality is also given by using parameter-dependent Lyapunov function method developed for the study of robust stability. A special linear star coupled dynamical network is also considered. The central subsystem must be unstable to stabilize the whole network under a special coupling. Several examples are given to illustrate the results. 相似文献
977.
文章介绍了监控类数据采集器的软件设计与原理.着重讨论了一种监控类通用数据采集器软件的实现技术和方法. 相似文献
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979.
980.